Improvement in pulley-blocks



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lJOSEPH W. NORCROSS, OF BOSTON, MASSACHUSETTS.

Letters Patent No. 113,688, dated April, l1` 1871.

IMPRGVEMENT IN PULLEV-BLOCKS.

The Schedule refen'efto in these Letters Patent and v-xzcia'king 'part'of the same.

To all whom it may concern Be it known that I, Josnrn W. Noncnoss, of Boston, in the county of Suffolk and State of Massachusetts, have invented a new and useful Improvement in Piulley-Blocks; and I do hereby declare the following to be a full, clear. and exact description thereof, which will enable those skilled in' the art to make and use the same, reference being had to th'e accompanying drawing forming part of this specification, in which drawing- Fignrel -represents a longitudinal cross-section of my invention.

Figure 2 isa plan view of myl invention where the metal frame is confined to the inside faces of the .cheeks of the pulley-block.

Similar letters'indicat-e corresponding parts:

This invention relates to pulley-blocks; and

Ihe invention consists of several features, as herein explained and described.

The letter A designates' the cheeks of the pulleyblock, which, in this example, are made of wood,

the grain being crosswise to the strain to preservev the edges of the cheeks from being split off or .readily worn away; but my invention can be used with cheeks of metal or any material.

The cheeks A are held together by double-headed metal pins B, one or more at ea'ch end, said pins being fonmed with shoulders C C, which come next to the inner faces of the cheeks so as to keep them the proper distance apart, the heads D of the pins coniing on the exterior of the cheeks and keeping them from being forced asunder.

I form the pins B and connect them 'withthe block by placing a metal-or other mold between the several cheeks andpartitions which compose the pulleyblock, xand screwing or otherwise securing the cheeks and partitions 4and mold'or molds firmly togetber.

The molds are so formed as to have spaces at the proper places for the formation of the pins, with their heads and shoulders D C opposite suitable openings the cheeks and partitions of the blocks; and when the molds are properly placed I pour in molten metal to .fill the spaces, and form the pins B and thei'rheads and shoulders.

By this construction I secure and adjust the cheeks or sides of pulley-blocks, and also the partitions where the block is double or treble, so as to avoid the defects and disadvantages that arise from the common methodof connecting the cheeks and partitions by rivets, among which defects are their want of firmness, and the difficulty of making the sides true and even, so that the vsheaves will revolve true.

can place rivets or bolts in the spaces where the pinsV are to befo'rmed and cast the pins around them so' as to combine them together. i

Another part-of my invention consists in combining with. the cheeks and partitions of a pulley-block ya' metal frame 'arranged' lengthwise of tlie block in such-a manner as to receive thevpins'B or other devices which connect the cheeks to each other, and form bearings for the journals of the sheaves, and sustain the strain to which the block is subjected,

. and which strain, owingr to the way the grain of the wood is arranged, crosswisel of the block, would be likely to break the wood.Y

The supporting-frame may be single or double,

`as preferred, and I Ahave shown' an example of a single frame in iig. Z'aud of a double flame in fig. l.

The letter E designates the frame.

In fig. 2 I have placed the frame E along the inside face of the cheeks ofthe block, sinking 4it in la* groove so as tomake it iiush with the surface of the cheek.

Each cheek has a like frame, E, and the frames are secured to the cheeksby means of the pins B, above mentioned, holes `being made in the 'frames for the pinsB and for the journals of thel sheaves.

1 In iig. l the frame E is doublethat is to say, a frameis placed on thel'outside as well as the inside of ,thecheeks, and the ends of the frames project beyond the ends of the cheeks and meet at F, where they protect the ends ofthe block.

The holes in the outer-frame E which receivethe pins B are conntersunk to receive the' heads D of the pins, so that ,the said heads will come flush with the face of the frame.

` The axis G of the. sueave is keyed to the block by a key, H, which is secured to theA block vby a screw inserted through au eye', I, formed therein at one end, so that the `axis is held stationary, and is also securely locked to the block.

By taking ut the screw and withdrawing the key I can turn the axis halt' round in the block and again secure it as before, thereby presenting au nnworn `surface to the action of the sheave when one side of the axis is worn down or flattened by use;

The pins B that hold the block together form seats for holding the beckets of the block.

The bechets J, at either end of this block, I make of rope or of wire;l In this example I have-shown 2. The key H, formed with an eye, I, when oombeckeiis made of rope and formed around the pins B. bned and operating with the axis G of a sheave which;y

What I claim as new, and desire to secure by Letrotates freely on its axis, substantially as herein shown ters Patent, isy Y 1. ,The strengthening-frame E, when secured to J W; NORCROSS. gether by means of the cast connecting-pins B, having external heads C and inner shoulders D, and cou- Witnesses: structed substantially in the manner herein shown andv O. WAHLERS, described. E. F. KASTENHUBEB.

and described. 1K 

